MQTT feature support in MQTT broker
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MQTT broker currently supports the following MQTT features and control packets.
| Feature or control packet | MQTT v3.1.1 | MQTT v5 |
|---|---|---|
| CONNECT Keep-Alive | Supported | Supported |
| CONNECT Will Messages | Supported | Supported |
| CONNECT Clean Start | Supported | |
| CONNECT Persistent session | Supported | |
| CONNECT Session Expiry Interval | Supported | |
| CONNECT Receive Maximum | Supported | |
| CONNECT Maximum Packet Size | ||
| CONNECT Topic Alias Maximum | ||
| CONNECT Request Response Information | ||
| CONNECT User Properties | Supported | |
| CONNECT Authentication Data | ||
| CONNECT Authentication Method | ||
| CONNECT Session Present flag (Persistent session) | Supported | Supported |
| CONNECT Server Generated Client ID | Supported | Supported |
| AUTH | ||
| PUBLISH QoS0 Delivery | Supported | Supported |
| PUBLISH QoS1 Delivery | Supported | Supported |
| PUBLISH QoS0 Offline messages for persistent sessions | Supported | Supported |
| PUBLISH QoS1 Offline messages for persistent sessions | Supported | Supported |
| PUBLISH QoS1 Flow control Currently, the broker sends out as many publishes as possible without waiting for the client to acknowledge them. |
Supported | Supported |
| PUBLISH QoS1 Message delivery retry | Supported | Supported |
| PUBLISH QoS0 Retain | Supported | Supported |
| PUBLISH QoS1 Retain | Supported | Supported |
| PUBLISH Correlation Data | Supported | |
| PUBLISH Response Topic | Supported | |
| PUBLISH Payload Format Indicator | Supported | |
| PUBLISH Message Expiry Interval | Supported | |
| PUBLISH Topic Alias | ||
| PUBLISH User Properties | Supported | |
| SUBSCRIBE | Supported | Supported |
| SUBSCRIBE Retain as Published | Supported | |
| SUBSCRIBE Retain Handling | Supported | |
| SUBSCRIBE Wildcards | Supported | Supported |
| SUBSCRIBE No Local | ||
| UNSUBSCRIBE | Supported | Supported |
| SUBSCRIBE $SYS topics | ||
| SUBSCRIBE Subscription Identifiers | ||
| SUBSCRIBE Shared Subscriptions | Supported | Supported |
| SUBSCRIBE Max subscriptions per client | ||
| PINGREQ | Supported | Supported |
| DISCONNECT | Supported | Supported |
| DISCONNECT Session Expiry Interval |